EP 2 103 249 A1 discloses an eye surgery microscope comprising an entity for measuring an ametropia of an inspected eye of a patient. The entity for measuring the ametropia comprises a wavefront sensor for analyzing wavefronts of light emerging from the eye and to determine the ametropia of the eye based on the analyzed wavefronts. The wavefront sensor is a Hartmann-Shack-sensor.
Indeed, the ametropia of the inspected eye can be determined relatively well with respect to multiple parameters using such a wavefront sensor, however, the wavefront sensor is expensive and requires a relatively large installation space and, therefore, may not be easily integrated into the microscope and further is sensitive to stray light.